Confirmed from sources
as the muff circuit Billy Corgan used for his "Siamese Dream"
guitar sound, this pedal is cloned from the exact same 1977 opamp-based
model used on the classic album. This version was the first muff
to break away from the traditional four-transistor circuit design,
using instead two opamps (a LM741 and JRC4558) that yielded a crunchier
hi-gain twist to the classic fuzz.